1. Field of the Invention
This invention relates to an apparatus for connecting sections of conduit to each other. Specifically, the invention relates to improved riser connectors for use in oil or gas wells.
2. Description of the Background Art
In oil or gas well completion systems, it is necessary to join the ends of adjacent riser pipes. Frequently this is done by means of a joint between two riser pipes commonly referred to as a riser or pipe connector. The riser connector is frequently subjected to powerful forces acting in many directions. If parts of the riser connector are not tightly fitted together, forces acting on the connector in different directions often cause internal wear in the connector, which increases the possibility of fatigue failure of the connector. To reduce looseness and internal wear in a riser connector, it is desirable to urge the connecting parts of the connector towards one another. This procedure is known as preloading.
Pipe connectors have been used in the art to connect together the ends of two pipes. In U.S. Pat. No. 4,114,928 (1978), Lochte disclosed a connector for connecting two conduits having a common axis. Lochte employs a toggle to preload the connection between the two conduits. The toggle expands to exert a force generally parallel to the common axis of the conduits, forcing one conduit towards the other, to connect the conduits and to preload the connection. The full magnitude of the preloading force is therefore transmitted through the components of the toggle. Since the typical magnitudes of preloading forces are of the order of millions of pounds, preloading forces may cause the toggle to deform and to lose its function. It is therefore desirable to design a riser connector for connecting two riser pipes which is less severely affected by such forces.